Promise vs Observable

 

console.log('start');

Promise.resolve().then(() => console.log('promise'));

console.log('end');

    const promise = new Promise((resolve,reject)=>{

      console.log("Promise executed");

      resolve(100);

      resolve(200);

      resolve(300);

    });

    promise.then((val)=>{

  console.log("Promise value: ", val);

 });

    const testobs = new Observable(sub=>{

      console.log("Observable executed");

      sub.next(200);

      sub.next(300);

      sub.next(400);

      sub.complete();

    });

    testobs.subscribe((val)=>{

      console.log("Observable value: ", val);

    });